I think what you need to do is open the computers Network Manager. Have it search for signals, and log in to yours.

Thanks very much FredMcD. Unfortunately all it did was say it couldn't find a signal. I clicked Troubleshoot and it seemed to search for a while, then advised me to get a friend to help! I've finished up changing the network key back to the old complicated one (fortunately I'd kept a copy) but it's very frustrating because I'm going to have to go through the whole thing again next time I want to use a device that requires the network key. Never mind. Thanks a lot for trying.

I've called the big guys to help you. Good luck.

Hi Margo65, If you have not set up your network over again it is possible to set up the wireless while connected to the ethernet cable. However best bet is to configure how Windows connects to the internet by trying to detect the wireless coming from the router.

Does your router have a control panel that you can access from the mobile device as well?

Netgear also has a support contact: http://support.netgear.com/general/co.../default.aspx

Thanks for this, guigs2. Unfortunately the Netgear support didn't get me anywhere because the terms it used bore no relation to what the computer came up with. I think the problem is in Windows (it's Windows 7 Professional). I can't access the router control panel from my mobile device, by the way. When I have time I'll try the Windows help website, but meanwhile I've reset the router with the old network key, so the computer can access the internet wirelessly as before. That's all I can do for now, and after all it does work ok. Thanks so much for trying to help me.

Delete the network information that is stored on the operating system and try to detect the wireless with a fresh start. Then store the new key.